1118880domain: NAppears in sequencesSum of divisors of k such that k and k+1 have the same number and sum of divisors.at n=16A054005Sum of aliquot divisors of Ramanujan's highly composite numbers.at n=33A072824E.g.f. A(x) satisfies A(x) = 1 - (1/x) * log(1 - x^2*A(x)).at n=8A392929